Water heater

ABSTRACT

A water heater apparatus includes an inner tank, an outer tank, heat bands disposed on the outside of the outer tank, an interior coil supplying water to the inner tank, and a heating element for heating water in the inner tank. The inner tank and outer tank are concentrically arranged with a labyrinthine passage in between, so that water spends an additional amount of time flowing in the passage while it is being heated by the heat supplied from the band heaters. The water heater apparatus can thereby provide heated water ready for delivery, as well as maintaining a start up heat.

CROSS REFERENCE TO RELATED APPLICATIONS

Not applicable.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

FIELD OF THE INVENTION

The present invention relates generally to an apparatus for providing heated water ready for delivery. More particularly, this invention is directed to an apparatus or device for heating water for immediate delivery as well as maintaining a start up heat.

BACKGROUND OF THE INVENTION

As noted in U.S. Pat. No. 4,242,569 to Kayser, hot water tanks are known which have inner and outer tanks for heating water.

In U.S. Pat. No. 4,860,728 to Nelson, a water heater is shown which includes an inner tank surrounded by an outer shell.

U.S. Pat. No. 5,006,689 to Kurachi et al. teaches inner and outer tanks along with a vacuum heat insulation layer and electrically heated bubble pump unit.

There is a need for an apparatus or device for quickly providing a stream of hot water, ready for delivery. Further, there is a need for an apparatus or device for heating water for immediate delivery as well as maintaining a start up heat.

SUMMARY OF THE INVENTION

From the foregoing, it is seen that it is a problem in the art to provide a device meeting the above requirements. According to the present invention, a device is provided which meets the aforementioned requirements and needs in the prior art. Specifically, the device according to the present invention provides an apparatus or device for quickly providing a stream of hot water, ready for delivery. More particularly, this invention is directed to an apparatus or device for heating water for immediate delivery as well as maintaining a start up heat.

The device according to the present invention includes an inner tank, an outer tank, heat bands disposed on the outside of the outer tank, an interior coil supplying water to the inner tank, and a heating element for heating water in the inner tank. The inner tank and outer tank are concentrically arranged with a labyrinthine passage in between, so that water spends an additional amount of time flowing in the passage while it is being heated by the heat supplied from the band heaters.

In use, water enters the unit through an inlet and travels through a coil that is suspended on the inside of the inner tank. Water then exits the coil and enters the outer tank, and then travels through a water channel that is formed with spacers placed between the outside of the inner tank and the inside of the outer tank. Water leaves the outer tank heated to the desired temperature.

A heating element in the inner tank heats the water inside the inner tank. The water inside the inner tank heats the water passing through the coil so as to keep the entire unit at a desired operating temperature, and is also a partial source of the hot water supply. Fresh water constantly passes through the inner tank when in use. The band heaters are controlled separately. The demand determines how many of the individual band heaters work at any given time during use.

Hot water is stored in the inner tank, the coil, the outer tank, and the water channel. When a small amount of hot water is needed, hot water is supplied from those areas. When the temperature cools, the band heaters are activated and water is heated as needed.

The flow of water passing through the inner tank is limited so that the heating element is not overwhelmed, and therefore can remain a heat source for the unit.

Metal strips form the water channel, and also act as a heat exchanger between the inner and outer tanks. A thermal jacket is placed on the outside of the unit to minimize heat loss and maximize the efficiency of the band heaters. After the band heaters are activated, the unit will produce as much hot water as desired with zero recovery time.

Other objects and advantages of the present invention will be more readily apparent from the following detailed description when read in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic side view of a water heater apparatus for quickly providing heated water, according to the present invention.

FIG. 2 is a schematic side view of the outside of the inner tank showing a labyrinthine passage former thereon, and usable in the apparatus of FIG. 1.

FIG. 3 is a schematic side elevational view of the outside of the outer tank having band heaters disposed therearound, and usable in the apparatus of FIG. 1.

FIG. 4A is an elevational view of a top plate for the inner tank, usable in the apparatus of FIG. 1.

FIG. 4B is an elevational view of a bottom plate for the inner tank, usable in the apparatus of FIG. 1.

FIG. 5A is a schematic cutaway view of the top plate assembly, usable in the apparatus of FIG. 1.

FIG. 5B is a schematic cutaway view of the bottom plate assembly, usable in the apparatus of FIG. 1.

FIG. 6A is an elevational view of the top plate for the outer tank, usable in the apparatus of FIG. 1.

FIG. 6B is an elevational view of the bottom plate for the outer tank, usable in the apparatus of FIG. 1.

FIG. 7 is an assembly view of another embodiment of the apparatus of FIG. 1, wherein a spiral separator separates the inner shell and the outer shell.

FIG. 8 is a perspective view of the inner tank of FIG. 7.

FIG. 9 is a side elevational view of the inner tank of FIG. 7.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 is a schematic side view of a water heater apparatus 100 for quickly providing heated water. The water heater apparatus 100 has an inner tank 140, an outer tank 120, and a plurality of heat bands 260 disposed on the outside of the outer tank 120. The walls of the inner tank 140 and outer tank 120 are broken away to reveal internal structures.

In FIG. 1, the water heater apparatus 100 includes an interior coil 160 supplying water to the inner tank 140, and a heating element 220 for heating water in the inner tank 140. The inner tank 140 and the outer tank 120 are concentrically arranged with a labyrinthine passage 740 (shown in FIG. 2) in between, so that water spends an additional amount of time flowing in the passage 740 while it is being heated by the heat supplied from the band heaters 260.

In FIG. 1, a pop off valve 320 is schematically shown passing through the uppermost wall of the outer tank 120. The inner coil 160 has an inlet 200 and an outlet 300 which communicates with the interior of the outer tank 120. The interior coil 160 has a small opening 180 which supplies fresh water from the interior coil 160 to the interior of the inner tank 140. Another small opening 280 is disposed in the uppermost wall of the inner tank 140, allowing water flow out of the inner tank 140. The interior coil 160 does not otherwise communicate with the interior of the inner tank 140. A heating element 220 extends into the interior of the inner tank 140 for heating water within the inner tank 140. Power lines and control circuitry for the heating element 220 are not shown, as such elements are conventional and would be understood by anyone having skill in the water heating element art. An outlet 240 supplies heated water from the interior of the outer tank 120 to a house or other location.

In a preferred embodiment, the water heater apparatus 100 is relatively small and extends only about 11 or 12 inches in diameter and about 18 inches in length, and the openings 180 and 280 are about one-eighth inch in diameter. However, the specific dimensions can be varied within the scope of the present invention, and all such variations are contemplated as being within the scope of the present invention.

In use, water enters the unit through an inlet and travels through a coil that is suspended on the inside of the inner tank. Water then exits the coil and enters the outer tank, and then travels through a water channel that is formed with spacers placed between the outside of the inner tank and the inside of the outer tank. Water leaves the outer tank heated to the desired temperature.

A heating element in the inner tank heats the water inside the inner tank. The water inside the inner tank heats the water passing through the coil so as to keep the entire unit at a desired operating temperature, and is also a partial source of the hot water supply. Fresh water constantly passes through the inner tank when in use. The band heaters are controlled separately. The demand determines how many of the individual band heaters work at any given time during use.

Hot water is stored in the inner tank, the coil, the outer tank, and the water channel. When a small amount of hot water is needed, hot water is supplied from those areas. When the temperature cools, the band heaters are activated and water is heated as needed.

The flow of water passing through the inner tank is limited so that the heating element is not overwhelmed, and therefore can remain a heat source for the unit.

Metal strips form the water channel, and also act as a heat exchanger between the inner and outer tanks. A thermal jacket is placed on the outside of the unit to minimize heat loss and maximize the efficiency of the band heaters. After the band heaters are activated, the unit will produce as much hot water as desired with zero recovery time.

FIG. 2 is a schematic side view of the outside of the inner tank 140 showing a plurality of spacers 340 forming a labyrinthine passage 740 on the inner tank 140. The spacers are preferably composed of metal, such as metal wire or metal strips. The intended direction of fluid flow is indicated by the arrows along the labyrinthine passage 740 in FIG. 2.

FIG. 3 is a schematic side elevational view of the outside of the outer tank 120, having a plurality of band heaters 360 concentrically disposed therearound. The upper portion of the outer tank 120 is broken away in this view. The band heaters 360 are selectively actuated to generate heat, and transfer the heat to the outer tank 120 when actuated. Power wires 720 are shown as being schematically connected to the respective ones of the band heaters 360, and any type of known control can be used for controlling power to each of the band heaters 360. For example, an ordinary thermostat can be used to turn all the heaters on or off, while a proportional controller can be used to selectively actuate fewer ones of the band heaters 360 when only a little additional heat is needed, and more of the band heaters 360 when a condition exists requiring substantially more heating.

FIG. 4A is an elevational view of a top plate 380 for the inner tank 140 (shown in dashed outline in this view). The top plate 380 has an outlet 300 for allowing passage of liquid from the inner tank 140 to the outer tank 120. There is additionally a small hole or bore 280 passing through the plate 380, permitting relatively small amounts of liquid to pass into or out of the inner tank 140. In a preferred embodiment, the bore 280 is approximately one-eighth inch in diameter; however, other diameters smaller than that of the outlet 300 can be used for the bore 280 without departing from the scope of the present invention. The top plate 380 has a notch 460 along one edge thereof, to create an inlet to the water channel.

FIG. 4B is an elevational view of a bottom plate 400 for the inner tank 140 (shown in dashed outline in this view). The bottom plate 400 has a central bore or aperture 760 which receives the heating element 220 (shown in FIG. 1) and a bore 780 which receives the inlet 200 (shown in section in this view). The bottom plate 400 has a notch 480 along one edge thereof, to create an outlet to the water channel. The water channel may be part of the labyrinthine passageway 740.

FIG. 5A is a schematic cutaway view of the top plate assembly, showing the top plate 420 for the outer tank 120 disposed above the top plate 380 for the inner tank 140. A pop off valve 320 is shown passing through the bore 300 of the top plate 420. FIG. 5A additionally shows a spacer element 340 disposed between the walls of the inner tank 140 and the outer tank 120.

FIG. 5B is a schematic cutaway view of the bottom plate assembly, showing the bottom plate 400 for the inner tank 140 disposed above the bottom plate 440 for the outer tank 120. Here, too, a spacer 340 is schematically shown between the walls of the inner tank 140 and the outer tank 120. The bottom plate 440 is shown having the inlet 200 and also showing an opening which communicates with an outlet 240 to a house or other destination. In this view, the heating element 220 is shown schematically and partially broken away, the heating element 220 passing through a bore 760 in the bottom plate 440 for the outer tank 120 and through a bore 800 in the bottom plate 400 for the inner tank 140.

FIG. 6A is an elevational view of the top plate 420 for the outer tank 120, as also shown in FIG. 5A. The pop off valve 320 is shown schematically in top elevation in this figure.

FIG. 6B is an elevational view of the bottom plate 440 for the outer tank 120, as also shown in FIG. 5B. The inlet 200 and the outlet 240 are also shown in this view. The heating element 220 is shown schematically in bottom elevation in this view.

FIG. 7 is an assembly view of an apparatus 500, which is another embodiment of the apparatus of FIG. 1, wherein a spiral separator 620 separates an inner shell 600 and an outer shell 520. Here, the parts are similar to those of the previous figures, and work in the same way, and include: the outer shell 520, end plates 540 and 560, the inner shell 600, and end plates 640 and 660. Here, the bottom plate 660 differs somewhat from the previous embodiment, in that a heater element fitting 680 is arranged to one side of the center, as is a pressure release valve fitting 720, and an inlet 700 is close to the center.

FIG. 8 is a perspective view of the inner tank 600 of FIG. 7. Here, the separator 620 is seen clearly forming a helical path along the outside of the inner tank 600.

FIG. 9 is a side elevational view of the inner tank 600 of FIGS. 7 and 8, also showing the separator 620. The separator can be formed of metal wire or plate.

The invention being thus described, it will be evident that the same may be varied in many ways by a routineer in the applicable arts. Such variations are not to be regarded as a departure from the spirit and scope of the invention and all such modifications are intended to be included within the scope of the claims. 

1. An apparatus for heating water, comprising: an outer tank having a circumferential wall, a top plate, and a bottom plate; an inner tank having a circumferential wall, a top plate, and a bottom plate; and said inner tank being disposed within said outer tank, a coil having a main body portion, an inlet, and an outlet; wherein said main body portion of the coil is disposed inside said inner tank, said inlet of the coil extends through the bottom wall of the inner tank and the bottom wall of the outer tank; a heating element extending into an interior of said inner tank; and an outlet conduit connected to said outer tank, and communicating with an interior of said outer tank.
 2. An apparatus for heating water as claimed in claim 1, further comprising a plurality of band heaters connected to an exterior of said outer tank.
 3. An apparatus for heating water as claimed in claim 2, further comprising a plurality of spacers disposed between said inner tank and said outer tank, forming a labyrinthine passage for fluid flow, so that all of the fluid flowing into said outlet conduit first passes through said labyrinthine passage.
 4. An apparatus for heating as claimed in claim 3, wherein said labyrinthine passage provides additional time for heat transfer to occur between said band heaters and said fluid.
 5. An apparatus for heating water as claimed in claim 3, wherein said plurality of band heaters are selectively actuatable, to selectively vary the amount of heat supplied to said outer tank.
 6. An apparatus for heating water as claimed in claim 1, further comprising a pop off valve disposed through an upper plate of said outer tank.
 7. An apparatus for heating water as claimed in claim 1, wherein said inner tank has a cylindrical wall, an upper plate and a lower plate; and said outer tank has a cylindrical wall, an upper plate and a lower plate.
 8. An apparatus for heating water, comprising: an outer tank having a circumferential wall, a top plate, and a bottom plate; an inner tank having a circumferential wall, a top plate, and a bottom plate; and said inner tank being disposed within said outer tank, a coil having a main body portion, an inlet, and an outlet; wherein said main body portion of the coil is disposed inside said inner tank, said inlet of the coil extends through the bottom wall of the inner tank and the bottom wall of the outer tank; a heating element extending into an interior of said inner tank; an outlet conduit connected to said outer tank, and communicating with an interior of said outer tank; a plurality of band heaters connected to an exterior of said outer tank; and an elongated spacer member helically arranged along the outside surface of said inner tank, forming a helical passage for fluid flow, so that all of the fluid flowing into said outlet conduit first passes through said helical passage. 